ACCRA  - Ghana’s main opposition party on Sunday alleged a “pattern of fraud” in the country’s tight presidential election, saying it had evidence that its candidate Nana Akufo-Addo had won the vote. The opposition’s claims came as partial official results showed the race almost neck-and-neck, while local media gave incumbent John Dramani Mahama a slight edge based on provisional results from nearly all districts. Ghana, a new oil producer with a booming economy, is seeking to live up to its reputation as a beacon of democracy in turbulent West Africa.

Observers from the Commonwealth, West African bloc ECOWAS and local group CODEO have all said the vote held over Friday and Saturday had appeared peaceful and transparent.

The opposition however issued a scathing statement alleging fraud.

“Indeed, we have enough concrete evidence to show that the 2012 presidential election was won by our candidate, Nana Akufo-Addo,” the New Patriotic Party said.

“We have noticed a pattern of fraud, where substantial numbers of votes are either added to the NDC (National Democratic Congress) candidate or subtracted from the NPP presidential candidate.”

It demanded an audit of collated vote figures as well as of data from the biometric verification machines used in the election before the results are officially announced.

Privately owned Joy News television, based on provisional results from 269 of 275 districts, said Mahama of the NDC party had garnered 50.66 percent of the vote and Akufo-Addo 47.76 percent.

The electoral commission was releasing results on its website, but the most recent numbers available included only 173 of 275 districts. Those results put Mahama at 49.61 percent and Akufo-Addo at 48.9 percent.

A run-off election is to be held on December 28 if no candidate receives more than 50 percent. There are a total of eight presidential candidates.

“We call upon our party members and the general public to ignore the tainted provisional results announced through the mass media,” the NPP said.

A crowd of about 200 NPP supporters sought to march on the electoral commission Sunday afternoon. They remained peaceful as they stood behind security forces who blocked a main road to the commission, shouting “we want justice,” an AFP correspondent reported.

Akufo-Addo has not spoken publicly, while Mahama earlier Sunday told journalists his team had “a fair idea” of the results based on its own tallies, but would wait for the electoral commission to make an announcement.

“We all will await peacefully the (commission’s) verdict and we will abide by whatever verdict the electoral commission gives,” said Mahama.

The 54-year-old took power after John Atta Mills died in July. Akufo-Addo, 68, a Britain-trained human rights lawyer and son of a former president, lost by less than one percentage point in 2008 polls.

Some analysts say the parties do not have major ideological differences, but the ruling NDC is seen as slightly centre-left while the NPP is viewed as more free market-oriented.

Ghana’s presidential and parliamentary polls were held on Friday, but polling stations in some areas re-opened on Saturday after problems with a new biometric system and late delivery of materials led to delays.

Elections since the return to civilian rule in 1992 have seen both parties voted out of office, establishing Ghana’s democratic credentials in a region that has had its share of rigged polls and coups.

Ghana is also a top exporter of cocoa and gold, with economic growth of 14 percent in 2011. Eight percent growth is expected in 2012 and 2013.

How to spend Ghana’s newfound oil money has been a key issue. Mahama has advocated a large investment in infrastructure, while Akufo-Addo has promoted his signature policy of free secondary education.

On the first day of the election on Friday, voting went smoothly in most areas, but a new biometric system requiring electronic fingerprints broke down in certain districts, resulting in long lines and frustration.

Materials arriving late also caused some polling stations to open far behind schedule. In areas affected by the two issues, election officials ordered polling stations to extend voting into a second day.